1. Technical Field
This invention is generally related to head gaskets for internal combustion engines. More particularly, the invention relates to multilayer metal head gaskets for internal combustion engines having an integrated sensor, such as a pressure sensor.
2. Related Art
In order to improve the control of an internal combustion engine, it is desirable to closely monitor the combustion process within the engine. It is most desirable to monitor the combustion process occurring within each of the cylinders of the engine (i.e., combustion pressure, temperature, etc.); however, it has not thus far been cost effective to incorporate such sensors, particularly combustion pressure sensors, into each of the cylinders, because of the machining required to incorporate the sensors into the cylinder block or cylinder head and the cost and packaging issues associated with multiple sensors, wiring harnesses, connectors and other items necessary to integrate such sensors.
It is desirable to integrate combustion sensors into the head gasket because the gasket itself is exposed to the combustion processes occurring in each cylinder, thereby eliminating a requirement for adding ports in the cylinder side wall or head in order to provide access to the combustion processes occurring in each cylinder. It is also very desirable to integrate combustion sensors and any necessary communication signal lines associated with them into multilayer metal head gaskets of conventional construction with a minimum of changes in the construction and technology currently used to make such gaskets. It is also very desirable to integrate a signal processing module or modules into the head gasket so as to minimize the distance over which the raw sensor signals must be transmitted prior to being processed, thereby minimizing issues associated with noise and/or signal loss, as well as minimizing the need for additional electrical hardware, such as wiring harnesses and connectors.
It is, therefore, an object of this invention to integrate combustion sensors into a multilayer metal head gasket of conventional construction. It is further an object of this invention to incorporate the sensor and associated signal lines into the spacing or distance layers of such a gasket. It is still further an object of this invention to incorporate a signal processing module into the integrated head gasket/sensor assembly.